Conventional magnetic data recording devices employ magnetic disk drives that include a magnetic storage media and a magnetic transducer referred to as a read/write head. The head is usually formed from a plurality of ferromagnetic structures that comprise materials such as nickel iron (NiFe) alloys for instance. The read/write head utilizes poles that are formed on opposite sides of the read/write head. In conventional read/write head arrangements, the poles are joined at one end of the read/write head that is referred to as the “yoke,” and are separated by a gap at an opposite end of the read/write head that is referred to as the “tip”. A wire coil that is wrapped around the poles near the magnetic disk provides a mechanism for driving magnetic flux from the read/write head.
In a conventional magnetic disk drive, data is written and read by a read/write head that is positioned adjacent to a magnetic platter or disk while the magnetic disk is rotated at high speed. The magnetic read/write head is mounted on a slider that positions the read/write head over a track on the surface of the magnetic disk where it is supported by an air cushion generated by the magnetic disk's high rotational speed. In order to increase the amount of data stored per unit of disk surface area more data must be written in narrower tracks on the disk surface.
Conventional read/write heads include a write pole that is employed to drive magnetic flux from the read/write head when data is written to a magnetic disk. In the fabrication of the write pole, a seed layer is employed. Optimal performance of the write pole in effecting the transfer of data to a magnetic disk is related in part to the thickness of the seed layer that is employed in the fabrication of the write pole.
With reference to FIG. 1 and FIG. 2, a current methodology used for forming a write pole includes: (1) the deposition of a seed layer 10 on a wafer 20; (2) the printing of a photoresist pattern 30 on the seed layer; (3) the cutting of a write pole trench into the photoresist; and (4) the plating of a write pole 40 in the trench. Subsequently, (5) the seed layer is removed everywhere but under the pole. FIGS. 1 and 2 respectively show cross sectional views of a wafer undergoing this process after the plating and seed layer removal steps. During the seed layer removal step, a portion 50 of the plated pole height is generally lost (see FIG. 2). The loss in pole height during the seed layer removal step may be about 1600 angstroms for an 800 angstrom seed layer. This level of pole height loss negatively impacts the performance capacity of the read/write head thus fabricated.
One possible solution to the above noted problem is to increase the thickness of the seed layer that is employed in the fabrication of the write pole since the high-moment seed used can improve read/write head performance. However, increasing the seed thickness means reducing the final pole height (because more seed thickness needs to be removed in the area that is not under the pole) or increasing the as plated pole height. Both of these conventional solutions would prove inadequate. Accordingly, a need exists for a method or process that facilitates the fabrication of a write pole of a desired height with an optimal seed layer thickness.